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Brassai
23-Apr-2014, 19:38
I have a couple of c.1908 lenses in shutter I need some info on. Both are in good condition. The first is a RR in CCC double pumper shutter (Century Camera Company). My question on this lens is about the f-stops. The scale reads (in this order left to right) 64, 32, 16, 8. My question is I'm assuming this is the old U.S. system, so f16 = f16, but f8 = f11 (wide open,) and f32 would equal f22. Is this correct?

Second lens is a Velostigmat Series 1 (6 in.) in a snazzy Volute shutter. Several questions here. First, what is a Series 1? I found info on Series 2, but not Series 1. Second question is about the f-stops. Are they likely U.S. stops? The scale reads, in order left to right, f6.8, f8, 11, 16, 22, 32, 44. Third, I got to looking at the scale and saw there is a second set of numbers above the first. OK, it's a convertible Tessar. The second scale begins over the f16 with f32, above f22 is f44, etc. until above f44 is f88. Would the f32 on this scale equal our f22? Finally, it's a convertible, but with which set of elements? Do I unscrew the front elements and use the rear, or is it the other way around?

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Louis Pacilla
24-Apr-2014, 09:05
Second lens is a Velostigmat Series 1 (6 in.) in a snazzy Volute shutter. Several questions here. First, what is a Series 1? I found info on Series 2, but not Series 1. Second question is about the f-stops. Are they likely U.S. stops? The scale reads, in order left to right, f6.8, f8, 11, 16, 22, 32, 44. Third, I got to looking at the scale and saw there is a second set of numbers above the first. OK, it's a convertible Tessar. The second scale begins over the f16 with f32, above f22 is f44, etc. until above f44 is f88. Would the f32 on this scale equal our f22? Finally, it's a convertible, but with which set of elements? Do I unscrew the front elements and use the rear, or is it the other way around?



You may want to look a bit harder as there is loads of information on this lens on the web and most in the usual places http://www.cameraeccentric.com/html/info/wollensak_9.html. Your Series I is early in that it's a f6.8 and they changed it to a f6.3 shortly after buying the design. Wollensak was a shutter manufacturer 1st then bought out The Rochester Lens Co. they made this design as well as several others, one being the the Vitax which was known as the Royal Portrait? I believe.
Anyhow it's a 2+2}{2+2 so it can suffer from low contrast and flair if the front cell is not well shaded so use of a hood is highly recommended. You use the convertible feature like all convertible lenses with the FL behind the iris for max image circle. You should have a combined FL of 6" and the front cell is 10"f 11 and the rear is 14" f16. I have a 6" f6.3 copy on on of my hand and stand cameras a Seneca 9 3A post card 5 1/2 x 3 1/2

The Series I got a face lift later down the road and became the Series Ia which resulted in better performance as they went with the Protar Series VIIa construction with glued groups of 4 elements per cell. So 4 }{4 which increased image circle and did away with the lower contrast & flair by doing away with the 8 air to glass surfaces of the earlier design.

Hope this helps.

desertrat
24-Apr-2014, 09:54
I use a series I Wolly on my 8X10. It exhibits low contrast and filling in of deep shadows with diffuse light when used wide open. But when stopped down to f32 or smaller, which is what I normally use for landscapes, this low contrast and filling in of deep shadows goes away. At small stops it behaves pretty much like my Dagor or T-R triple, fully cemented designs.